Are you frustrated that you dropped only a few pounds following a new diet, but your best friend lost almost 30? Why did the probiotics that helped your sister’s bloating sensation do nothing for you? Your coworker swears that going gluten-free made his joint pain disappear, but you just came away craving more bread and pasta. In a world where we expect personalized products and services delivered promptly to our screens and doors, medicine is not even close to bringing this level of experience. Why does precision medicine in the 21st century remain so elusive?

We are using an old framework to resolve the most common contemporary health problems. Last century, antibiotics revolutionized medicine. conquering sickness and death very effectively. More recently, there has been a seismic shift on how we get sick and die. Chronic conditions like cardiovascular disease, cancer, dementia, autoimmune diseases, and mental health issues have been at the top of the list for several decades all over the world. These problems are hard to “cure,” hence the term “chronic,” meaning long-lasting or prolonged.

The relationship between cause and consequence for infectious diseases is straightforward. The symptoms go away after wiping out the bugs (virus, bacteria, parasites). But a simple and direct cause-and-effect rarely exists for chronic medical problems. Most often, these result from a complex web of factors. It could be related to a genetic predisposition, a nutritional deficiency, a reaction to food or a chemical product, a dysfunctional hormonal response, excessive inflammation, an uncontrolled immune response, an infectious agent, or microbiome imbalances. Chronic disease happens when one, but usually more than one, of these factors are disturbed. So fixing just one of these underlying factors is unlikely to effectively treat the problem.

Standard medicine versus precision medicine

Standard care is based on clinical studies that take groups of people and try to figure out treatments that would work for most of them — that is, what would work best for the average person in those groups. But if you look closely at the data, you’ll see a variety of individual responses. As a primary care doctor, I often see a treatment leading to extraordinary results for one patient, but causing terrible side effects for another. What works for you may not work for your best friend or even your sibling. We are all unique in many different ways. The message is simple: not one size fits all. When dealing with chronic disease management, it is often a game of trial and error, far from precision.

Lifestyle change as precision medicine

Many companies want to understand these complexities, creating personalized plans based on our genetics, biomarkers, and lifestyle. The future of medicine will likely include the analysis of several different data points, providing a picture of what could work best for each individual, but modifying a few biological pathways is unlikely to lead to better well-being. The reason is simple: we cannot prevent or reverse these diseases without a lifestyle focus. This may not sound as sexy as using the most advanced algorithm from the best artificial intelligence computer out there, but it does work for most of us. A good prescription to prevent and treat chronic medical problems would include: eating a non-processed, colorful, mostly vegetarian diet; exercising daily; getting plenty of sleep; connecting with friends and family; and setting up time for relaxation. Each of these strengthens the foundation of that web of factors that keeps us well. A healthier lifestyle supports and creates the resilience we need to sustain the inevitable exposure to life’s wear and tear.

The bottom line: Precision medicine starts at home

We often see passionate opinions about the right diet, supplements, or medication from friends, family, famous people, and even medical providers and experts. But preventing and managing chronic illnesses usually requires more than one simple intervention. And it usually does not require the latest, most technological advancement in science, or the latest health fad trending in social media. Precision medicine starts by spending more time taking a look at what is on your plate, how much you move, and making sure you rest and sleep. I have seen many of my patients creating health and reversing chronic diseases using these tools. The challenge lies in changing behavior, which is not easy to do. If you cannot do it by yourself, talk to your doctor, or consider having a health coach to help you move you toward a healthier lifestyle. Accountability may be what you need to get you healthy.